Flame conveying tubes or wave tubes for ignition devices for gas burners

ABSTRACT

The invention relates to an ignition device for gas burners comprising a flame conveying tube or wave tube conveys a combustible gas to the outlet of the tube and a capillary bore auxiliary tube passing up the wave tube to convey gas to the end of the wave tube for ignition to maintain the ignition of the flame from the wave tube.

United States Patent Huguet [4 1 Mar. 21, 11972 [54] FLAME CONVEYING TUBES OR WAVE TUBES FOR IGNITION DEVICES FOR GAS BURNERS [72] Inventor:

[73] Assignee: Application Des Gaz, Paris, Seine, France [22] Filed: Mar. 16, 1970 [21] Appl. No: 19,677

Alain Huguet, Lyon, France [52] U.S.Cl ..431/254,431/l9l,431/277 [51] lnt.Cl ..F23q 2/16' [58] Field of Search ..43l/254,191, 192, 193, 273,

[56] References Cited UNITED STATES PATENTS 1,755,746 4/1930 Perrera ..43l/277 X 2,015,405 9/1935 Leins ..43l/l92 2,078,576 4/1937 Lachetto ..431/254 2,661,798 12/1953 Clevenger et al. ..43 l/202 X Primary Examiner-Edward G. Favors Attorney-Alexander & Dowell [5 7] ABSTRACT The invention relates to an ignition device for gas burners comprising a flame conveying tube or wave tube conveys a combustible gas to the outlet of the tube and a capillary bore auxiliary tube passing up the wave tube to convey gas to the end of the wave tube for ignition to maintain the ignition of the flame from the wave tube.

5 Claims, 3 Drawing Figures FLAME CONVEYING TUBES OR WAVE TUBES FOR IGNITION DEVICES FOR GAS BURNERS This invention relates to ignition devices in which a flame produced at one of the ends of a tube is moved over the length of the latter to arrive at a burner which it is desired to ignite.

Tubes of the kind referred to known as wave tubes have been used in particular to connect the burner to be ignited either to a burner already operating or to a pilot light. In such cases it is the gas of the burner to be ignited which circulates in the tube before becoming ignited at the other end of the latter the flame progressing in'the opposite direction to reach the burner concerned.

The present invention has as its object anignition device for gas burners, characterized in that it comprises a flame conveying tube or wave tube, means to cause a current of combustible gas to circulate in this tube and means to ignite this current at one point of the tube so that the flame so obtained progresses towards the outlet end of this tube to provide a lighting point.

According to another feature of the invention there is associated with the flame conveying tube or wave tube an auxiliary tube of smaller diameter passing through the combustible gas and substantially unmixed with air and which emerges in the immediate vicinity of the outlet end of the wave tube so that as soon as theflame circulating in this latter has reached the aforesaid end it ignites a pilot flame at the end of the auxiliary tube in order to ensure the stability of the composite flame of the two tubes thus overcoming the phenomena of instability or the emission of explosive mixtures which occurs in the wave tube when the air is in excess in relation to the combustible gas.

The actual ignition mechanism may be of any suitable kind. It may be realized in particular by means of a serrated wheel and a lighter flint or by means of-a piezoelectrical element. By whatever means are employed experience shows that the flame which this mechanism effects is the wave tube progresses in in a regular manner to the interior of the latter and that the possible phenomena of instability only appears when this flame has reached the outlet end of the tube. As in the preferred embodiment of the invention the pilot flame is ignited at this moment, the aforementioned phenomena cannot result complete extinction rendering the device ineffectual.

The invention will be described with reference to the accompanying drawings:

FIG. 1 is a vertical section of anignition device according to the invention provided with a serrated wheel and flint mechanism for ignition;

FIG. 2 is a section on line "-11 (FIG. 1);

FIG. 3 is a detail section to a large scale on line III-III (FIG. 1).

The device shown comprises a reservoir 1, for example, made of a plastics material for containing a combustible gas in a liquefied state such as butane. The filling valve is shown at 2 As shown in FIG. 2 the serrated wheel 17 is mounted on the spindle 18 between a cylindrical crosspiece 19 and a drive roller 20, the faces opposite the serrated wheel 17 and the roller 20 being provided with racketteeth in known manner. On the spindle 18 there may also slide freely the two arms of a pushbutton 21 these latter being slotted for this purpose with longitudinal slits 21a (see FIG. 1). As shown the pushbutton 21 passes through, in a free sliding manner, the sleeve 11. Its guiding is completed by a bearing 22 carried by the part 13 and which also passes the slits 21a. The pushbutton 21 is connected to the drive roller 20 in any suitable manner, not shown. It may, for example, be assumed that the roller comprises a radial notch in which a pin integral with the adjacent arm of the pushbutton engages. The essential feature is that when the pushbutton 21 is pushed from left to right in FIG. 1 the roller 20 is driven in an anticlockwise direction this latter driving in its turn the roller 17 which acts on the flint 14 to produce a shower of sparks in the direction of the tube 10 which is provided with an opening 10b for the passage of these latter.

Two springs 23 are attached respectively to a lug 21b on one of the arms of the pushbutton and in a corresponding slit 13b and at 3 the outlet valve screwed into a stopper 4 itself inserted by screwing onto the upper end of the reservoir 1. There is shown at 5 and 6 the joints suitable for ensuring gas tightness. The valve 3 has on known manner a tubular delivery stem 7 through which the gas leaves when this stem is lifted against a suitable spring. On the stem 7 there is mounted a plug 8 to engage a screwed tube 9 pierced by an outlet orifice 90. On the cylindrical periphery of the tube 9 is fitted a tube 10 perforated in the vicinity of this tube with air inlet openings such as 10a.

On the stopper 4 there is mounted in any suitable manner (for example, by means of radial screws, not shown) a sleeve 11 the opposite end of which is closed by a cap 12. This cap comprises at its center a boss 12a suitably bored for the sliding passage of the tube 10. This sleeve 11 encloses a member 13 having a lateral bore 13a adapted to receive a lighter flint 14, a pressure spring 15 and a regulating screw 16. The flint 14 is applied against a serrated wheel 17 mounted on a spindle 18 fixed to the part 13.

of the part 13 to return the pushbutton 21 to its outer position as shown in FIG. 1. A suitable system of stops, not shown, limits the return movement of the pushbutton 21.

The part 13 also carries in the base a transversal pin 24 on which is pivotally mounted a lever 25 with two arms at right angles. One of the arms of this lever is arranged so as to be pushed back by the pushbutton 21 while the other which is bifurcated passes under the plug 8 in order to lift it.

The tube 9 houses a tube 26 of small diameter (capillary tube) which is mounted inside the tube 10 to terminate adjacent the level of the-upper end of the latter. As shown in FIG. 3 this tube 26 is centered in respect of the upper end of the tube 10 by means of a metal wire bent in the form of two concentric rings 27a and 27b the first lodging in an inner groove 10c of the tube 10 while the second surrounds the tube 26.

The operation is as follows:

At rest the springs 23 keep the pushbutton 21 in the position shown in FIG. 1 (outermost position). The stem 7 of the gas outlet valve 3 is lowered to the closing position of this valve the vertical arm of the lever 25 being in its extreme left position.

If the pushbutton 21 is actuated the serrated wheel 17 is driven and a shower of sparks is produced which penetrates into the tube 10 through the opening 10b. At the commencement ofthe movement of the pushbutton however the lever 25 has raised the plug 8 with the stem 7 thus opening the valve 3. The gas has therefore flowed to the inside of the tube 9 and has escaped through the orifice 9a of this latter giving rise to a jet which ignites on contact with the sparks, the necessary air entering through the openings 10a (and additionally through the opening 10b). It should be noted that the raising of the plug 8 has lifted the tube 10 with the tube 26 which is integral therewith.

The flame which thus appears level with the serrated wheel 17 rises progressively in the tube 10 which therefore operates as a wave tube its feeding being ensured by the jet of gas coming from the tube 9 mixed with the air admitted through the openings 10a. This flame arrives at the upper end of the tube 10 where it immediately ignites the gas jet leaving the tube 26 and coming from the inner space of the tube 9. There appears therefore at the end of the tube 10 a composite flame constituted by a pilot flame or pilot light of small dimensions which burns at the end of the tube 26 without additional air coming from the latter and on the other hand a larger flame or main flame coming from a very rich mixture of air and which is established around the jet from the tube 26. If by reason of the large quantity of air which the mixture coming out of the tube 10, 11 contains there is produced in the latter the phenomena of explosive combustion leading to the blowing out of the main flame or if this latter lacks stability and goes out at the wrong time its re-ignition is immediately ensured in all cases by the pilot flame. The device may therefore be used with the assurance of its satisfactory operation under all conditions.

It will be understood that the ignition mechanism used may be of any kind. It is the same with the cartridge system combined with the device. The tube of small diameter 26 could if necessary have an air admission system on condition that the proportion of air thus admitted is small in order to ensure the stability of the pilot flame. It is in no way indispensible for the tube 26 to be centered in respect of the tube nor for this latter to rise at the time of operating the device.

What we claim is:

1. An ignition apparatus comprising:

a wave tube having a first end and a second end, said wave tube being formed with at least one lateral air inlet opening and with a lateral aperture disposed between said air inlet opening and said first end;

a gas nozzle disposed in said second end of said wave tube to direct a combustible gas jet into said wave tube and substantially coaxially to same, said gas jet drawing air through said opening to form therewith an inflammable mixture which flows through said wave tube towards the first end thereof;

a spark-producing mechanism disposed in front of said aperture to project sparks therethrough;

an auxiliary tube disposed within said wave tube, said auxiliary tube having a first end and a second end with said first end of said auxiliary tube being adjacent and substantially coaxial to the first end of said wave tube and opening in the same direction;

a gas chamber communicating with said gas nozzle and with said second end of said auxiliary tube to supply a combustible gas to both;

a liquefied gas cartridge associated to said gas chamber to supply combustible gas thereto;

valve means interposed between said cartridge and said gas chamber;

and means to simultaneously actuate said valve means and said spark-producing mechanism so as to open said valve means while projecting a burst of sparks through said aperture to ignite said inflammable mixture and to thus produce a flame which advances through said wave tube towards said first end thereof until it issues therefrom and ignites the gas issuing from the first end of said auxiliary tube to form there a pilot flame. In an apparatus as claimed in claim 1:

support to which said liquefied gas cartridge and said spark-producing mechanism are secured, said wave tube being longitudinally slidable in said support; said gas nozzle, said auxiliary tube and said gas chamber being secured to said wave tube to fonn therewith a slidable unit;

said valve means having a longitudinally movable tubular actuating stem which forms at the same time a gas outlet for said valve means;

and said movable unit being coaxially secured to said tubular actuating stem to be displaced therewith to open said valve means, with said tubular member communicating with said gas chamber.

3. An ignition apparatus comprising:

a wave tube having a first end and a second end;

means to inject an inflammable mixture of combustible gas and air into the second end of said wave tube to cause said mixture to flow through said wave tube towards said first end thereof;

means to ignite said inflammable mixture within said wave tube at a distance from said first end thereof, the flame thus produced advancing through said wave tube towards said first end until it issues therefrom;

an auxiliary tube of smaller diameter than said wave tube, said auxiliary tube having a first end and a second end, with said first end opening adjacent the first end of said wave tube; and means to in ect a combustible gas substantially free of air into the second end of said auxiliary tube so as to cause said gas to be ignited at said first end of said auxiliary tube by the flame issuing from the first end of said wave tube and thus to form a pilot flame.

4. In an ignition apparatus as claimed in claim 3, said first end of said auxiliary tube being disposed within said first end of said wave tube and substantially coaxially thereto.

5. An ignition apparatus comprising:

a wave tube having a first end, a second end, a lateral ignition aperture situated at a distance from said first end thereof but spaced from said second end thereof, and at least one lateral air inlet aperture adjacent said second end;

a gas nozzle closing said second end of said wave tube and supplied with a combustible gas under pressure to direct into said wave tube a high velocity gas jet substantially coaxial to said tube, said jet drawing outer air through said air inlet aperture to form therewith an inflammable mixture which flows through said tube towards the first end thereof;

and a flint-and-wheel spark producing mechanism disposed in front of said first aperture of said wave tube to project sparks therethrough so as to ignite said inflammable mixture, the flame thus produced advancing through said wave tube towards said first end thereof until it issues therefrom. 

1. An ignition apparatus comprising: a wave tube having a first end and a second end, said wave tube being formed with at least one lateral air inlet opening and with a lateral aperture disposed between said air inlet opening and said first end; a gas nozzle disposed in said second end of said wave tube to direct a combustible gas jet into said wave tube and substantially coaxially to same, said gas jet drawing air through said opening to form therewith an inflammable mixture which flows through said wave tube towards the first end thereof; a spark-producing mechanism disposed in front of said aperture to project sparks therethrough; an auxiliary tube disposed within said wave tube, said auxiliary tube having a first end and a second end with said first end of said auxiliary tube being adjacent and substantially coaxial to the first end of said wave tube and opening in the same direction; a gas chamber communicating with said gas nozzle and with said second end of said auxiliary tube to supply a combustible gas to both; a liquefied gas cartridge associated to said gas chamber to supply combustible gas thereto; valve means interposed between said cartridge and said gas chamber; and means to simultaneously actuate said valve means and said spark-producing mechanism so as to open said valve means while projecting a burst of sparks through said aperture to ignite said inflammable mixture and to thus produce a flame which advances through said wave tube towards said first end thereof until it issues therefrom and ignites the gas issuing from the first end of said auxiliary tube to form there a pilot flame.
 2. In an apparatus as claimed in claim 1: a support to which said liquefied gas cartridge and said spark-producing mechanism are secured, said wave tube being longitudinally slidable in said support; said gas nozzle, said auxiliary tube and said gas chamber being secured to said wave tube to form therewith a slidable unit; said valve means having a longitudinally movable tubular actuating stem which forms at the same time a gas outlet for said valve means; and said movable unit being coaxially secured to said tubular actuating stem to be displaced therewith to open said valve means, with said tubular member communicating with said gas chamber.
 3. An ignition apparatus comprising: a wave tube having a first end and a second end; means to inject an inflammable mixture of combustible gas and air into the second end of said wave tube to cause said mixture to flow through said wave tube towards said first end thereof; means to ignite said inflammable mixture within said wave tube at a distance from said first end thereof, the flame thus produced advancing through said wave tube towards said first end until it issues therefrom; an auxiliary tube of smaller diameter than said wave tube, said auxiliary tube having a first end and a second end, with said first end opening adjacent the first end of said wave tube; and means to inject a combustible gas substantially free of air into the second end of said auxiliary tube so as to cause said gas to be ignited at said first end of said auxiliary tube by the flame issuing from the first end of said wave tube and thus to form a pilot flame.
 4. In an ignition apparatus as claimed in claim 3, said first end of said auxiliary tube being disposed within said first end of said wave tube and substantially coaxially thereto.
 5. An ignition apparatus comprising: a wave tube having a first end, a second end, a lateral ignition aperture situated at a distance from said first end thereof but spaced from said second end thereof, and at least one lateral air inlet aperture adjacent said second end; a gas nozzle closing said second end of said wave tube and supplied with a combustible gas under pressure to direct into said wave tube a high velocity gas jet substantially coaxial to said tube, said jet drawing outer air through said air inlet aperture to form therewith an inflammable mixture which flows through said tube towards the first end thereof; and a flint-and-wheel spark producing mechanism disposed in front of said first aperture of said wave tube to project sparks therethrough so as to ignite said inflammable mixture, the flame thus produced advancing through said wave tube towards said first end thereof until it issues therefrom. 